Nervous system Flashcards
What does the nervous system do?
coordinate behaviour
respond to surroundings
Use of neurons
carry electrical impulses
Neurones adaptations
many dendrites: connect to more, pass more msg
myelin sheath: insulates impulses, speeds up impulse conduction
what are synapses, how do they work
gap between neurones
neurotransmitters are released to pass electrical impulses in a chemical way
post- receptors synapse membrane doesn’t allow backflow of impulses
electric current triggered and is transmission is continued
possible problems with synapses
interfered by other imitating or blocking chemicals
v drugs to deal
3 types of neurones
sensory, relay, motor
components and uses of CNS
brain + spinal cord
take in sensory info, instruct body to work
flow chart from stimulus to response
stimulus → receptor cells → sensory neurone → CNS (relay neurone) → motor neurone → effector → respons
spine isnt the same as spinal chord
types of receptors
eyes (light), ears (sound), nose (chemical), pain, pressure (KE / chem), temperature (thermal)
what’s a reflex arc
it’s the nerve pathway that underlies our unconscious reflexes
rapid and automatic, involuntary
avoid danger, protect
how is a reflex arc different from a normal reaction
a reflex arc doesn’t involve the brain, only spinal cord
What is homeostasis
Maintenance of a constant internal environment
Body temp & water content
What does co-ordinated response require
Stimulus, receptor, effector